Installation and Operation
Page 4-12
Owner’s Manual
TVM450/S/TVM550/S/TVM550II/TVM550IIS
Auxiliary Audio Processing
1. To select this mode, press the AUX AUDIO pushbutton (19) until the AUX
AUDIO LED (7) lights.
NOTE
This input may also be activated by connecting the CTL terminal (32) on the
module rear panel to ground.
2. While watching the AUDIO LED strings (2, 3, and 4), adjust the LEVEL po-
tentiometer (20) until the first red LED just lights.
TEST TONE
The handy built-in test tone is for checking the aural modulation at the 4.5 MHz
OUT terminal.
Checking the 4.5 MHz Aural Signal.
To test the DSG2000 aural signal, press the TEST TONE pushbutton (17) until the
TEST TONE LED (5) lights, and connect a spectrum analyzer to check for the
Bessell null point. No adjustment is possible.
External Modulator
When the BTSC is connected to an external modulator, the test tone is used to
calibrate the aural modulation level.
CHANGING TO BTSC OUTPUT OPERATION
The DSG2000 module is set at the factory for video output at the VIDEO/BTSC
OUT connector. To change to BTSC output:
1. Disconnect power, and remove the unit top cover.
2. There are two black-insulated wires jumped across the VIDEO/BTSC OUT
and VIDEO IN connectors inside the unit. Cut them both near the middle.
3. Locate the Digital BTSC Stereo Processor PC board (the large one), and
trace the heavy cable from the VIDEO/BTSC OUT connector to where it
ends near this board.
4. Remove the insulation covering the TMP connector at the end of the cable.
5. Plug the TMP connector into J1 on the Stereo Processor board.
6. Make sure the wires cut in step 2 do not interfere with other components or
cables (tape the ends, if necessary), and reinstall the unit top cover.
To revert to video output, reverse this procedure.
CHANGING TO COMPOSITE OUTPUT
To change to composite output at the 4.5 MHz OUT connector, jumper connec-
tions on the FM PC board must be changed (see Table 4-3).
